2017 6.6L Duramax L5P Diesel Engine

Gale Banks Weighs In on GM’s Long-Awaited Entry in the Consumer-Diesel Performance Battle

Unbeknownst to many of you, we have been running and testing a defense-market version of the all-new, ’17 6.6L Duramax L5P engine on the dyno since late 2015. Based on what we’ve learned during this time, trust me, you’ll be be impressed with the consumer version of this powerplant.
With the exception of the bore and stroke, virtually every part of this engine is new. Designed by a GM Global Propulsion Systems team that’s led by a duo of engineers who each has decades of experience in diesel design and high performance, the engine is improved from the centerline of the crankshaft out.

With L5P’s 445 hp and 910 lb-ft of segment-leading torque, it appears GM’s truck guys have entered and are expecting to win the torque war (and, ultimately, the heavy-towing battle) being waged by Ford and Ram. So, with the exception of the bore-center distance and the valve-stem centerline locations, very little of the Isuzu design remains. Having held a number of records with our Duramax-powered Pro Stock truck and our Banks Sidewinder Top Dragster, we knew what we wanted improved—and it’s like they read our minds.

The block, forged-steel crankshaft, main-bearing caps, rods, aluminum pistons, oil pump, water pump, and head gaskets are all bigger, stronger, and more capable than the components of previous versions. The high-pressure, common-rail direct-injection fueling system is more refined and capable of supporting a lot more power, as is the variable-geometry turbocharger. But the aluminum cylinder heads are really something else. Wow! I call them the 100hp heads, as they truly flow that well!

While we’re developing Marine, Motorsports, and Military versions of this engine, I’m confident that in the consumer sector, the 6.6L Duramax L5P will put ’17 Chevrolet Silverado and GMC Sierra 2500HDs and 3500HDs directly in the hunt to meet or possibly raise the bar for 1-ton pickup trucks’ towing capability. The wait is over, and GM has brought us an engine I think is going to make its presence known in a very big way.

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| Gale Banks Engineering has been secretly working with GM’s long-awaited, newest 6.6L diesel engine for quite some time. Enjoy this external view of the Duramax L5P V-8 and stay tuned to Diesel Power and trucktrend.com for a full reveal and details of its inner workings.